Composition roof covering



July 30, i935. s. oLsEN 2,009,812

COMPOSITION ROOF1 COVERING Filed Nov. l5, 1934 jffovvveg- Patented July 30, l1935 UNITED STATES PATENT OFFICE 6 Claims.

This invention relates to improvements in a waterproof substantially reproof composition which may be used as a roof covering, and refers specifically to a composition comprising a plurality of overlapping mica flakeseach of which is covered by a relatively thin film of asphalt or the like, which binds adjacent flakes together.

The utility, objects and advantages of my invention will be apparent from the accompanying drawing and following detail description.

In the drawing, Fig. 1 is a face view of a roong shingle which may be constructed of the composition comprising my invention.

Fig. 2 is a side elevationalview of the shingle illustrated in Fig. 1 showing a tapered construction.

Fig. 3 is a longitudinal sectional view taken on line 3 3 of Fig. 1.

Fig. 4 s a similar sectional view of a slightly modied form of a shingle.

Fig. 5 is an enlarged fragmentary sectional detailed view illustrating the asphalt unitedmica overlapping akes comprising the composition.

Fig. 6 illustrates another modified form of roof covering constructed of the composition comprising my invention.

Referring in detail to the drawing, I indicates a shingle constructed of the composition comprising the concept of my invention. The shingle which may be of conventional shape and general outward appearance and, for the purpose of illustration, is shown as being of tapered construction having a butt end 2 and tapered thin end 3, the butt end, of course, being exposed to the weather, may be coated with a` layer of asphalt in which slate granules of desired size and color may be embedded.

As a featre of my invention the body of the shingle I is constructed of a mixture of mica iiakes, of from four to approximately forty mesh and asphalt, the individual ilakes being coated with a thin lm of asphalt. A-shingle of this type, not containing vegetable or animal ber which could burn readily when saturated, is extremely re resistant. The shingle, rooting element, or sheet constructed of mica and asphalt, unlike conventional types of roofing materials which contain light saturating oils which eventually evaporate leaving a dry sheet exposed to the elements, will not dry out. crack, or cause a leaky roof. In addition, the shingle is waterproof, lasting, economically manufactured, ilexible, strong and light in weight. It will not expand or contract unduly and may be applied to the art.

. Application November 15, 1934, serial No. 753,143

the roof in any of the manners of application of .conventional roofing shingles, slabs or sheets. In manufacturing the roofing shingle l, the mica ilakes are thoroughly coated with heated asphalt making a mixture having the consistency 5 of dough. This dough-like mass of coated mica flakes may be formed into a sheet', the same being subjected to pressure between squeeze rolls or the like, which rernoveI the excess asphalt leaving a relatively thin lm of asphalt covering each of l0 the individual iiakes. The pressure of the squeeze rolls and the temperature Vof the asphalt during the squeezing operation may be so controlled as to bring the proportion of mica to asphalt from approximately 30 parts by weight of 15 mica to 70 parts by Weight of asphalt. Mica in its natural state is of a relatively rock-like structure and is extremely dense. The specific gravity of this mica is in the neighborhood of 2.9. However, when the mica is reduced to sheet or 20 flake form, the specic gravity of the resulting mass is reduced as much as ten times. Consequently, although in the example mentioned above, the asphalt predominates in weight, in volume of the resulting composition the mica predominates. Hence, a composition which contains parts mica and 70 parts asphalt by weight will byvolume be predominantly mica. By subjecting the sheet to pressure, the mica akes will substantially all be disposed in planes 30 parallel to each other and parallel to the surface of the sheet as shown best at 4 in Figs. 3, 4, 5 and 6, the individual mica flakes being adhesively united to each other by the relatively thin films of asphalt which coat each flake. After the squeezing operation the sheet may be cooled in any suitable manner familiar to those skilled in 'I'he sheet or portions thereof may then be coated with asphalt as shown at 5 in Figs. 3, 4 and 6, and a layer of granules 6 comprising slate 40 or the like may be embedded in the asphalt coating 5. The sheet may then be cut into individual shingles as shown in Figs. 1, 2, 3 and 4 or, if desired, slabs of multi-butt elements may be cut therefrom.

Referring particularly to Fig. 4, a modied form of my invention is shown, the reference numeral I' indicating a shingle element comprising the same composition as shingle I with the addition of a back of saturated roong felt or other saturated fibrous sheet 1. The felt side may be surfaced with powdered mica to prevent sticking or discoloration. The roof covering, if desired, may be constructed in the form of a continuous sheet as indicated at I in Fig. 6. In this form of my invention the body of the sheet may be backed by a brous sheet 8, similar to sheet 1, and the composition comprising the sheet I" may be similar to shingles I and I.

By the use of the forms of my invention shown in Figs. 4 and 6, an extremely strong roof covering is provided which is of light weight. The backing sheets 'I and 8 impart high insulating qualities to the rooting and being covered by micaasphalt composition, the ilreproof and waterproof characteristics of the roof covering as a whole are increased.

It has heretofore been deemed impractical to use asphalt or the like having a melting point above 220 F., for roof covering, slabs, shingles or the like, because of its brittleness. In making rooiing elements of the composition comprising my invention, an asphalt of much higher melting point may be used, as well as those of the usual range. The brittleness of the higher melting point asphalts does not impart undue brittleness to the composition because the asphalt is present in relatively thin lms which coat relatively thicker, stronger, more iiexible mica iiakes. In other words, the volume of the composition sheet. slab or shingle is predominantly mica and the resulting physical characteristics of the composition partake principally of the properties of the mica, the asphalt characteristics not exhibiting themselves to any marked degree with respect to brittleness because of the thinness of the film. This phase of my invention can be readily visualized by reference to Fig. 5 wherein the composition is shown in section, the asphalt being shown in just sufllcient quantity to adhesively unite adjacent flakes of mica.

One of the principal objections to the usual asphalt and felt shingle is that it is extremely flexible and the ends of a shingle so constructed are easily raised, as for instance, by a high wind blowing on the roof. Shingles or roof coverings made from my composition, which because of the presence of the mica in, such relatively large quantities, are comparatively rigid and are not easily flexed or displaced by such forces as wind. This is increasingly true of the tapered type of my shingle.

It is to be understood, oi' course, that although a roof covering comprising 30 parts by weight of mica and parts by weight of asphalt may be used with good results, I do not wish to be limited to these speciilc proportions since the composition is equally efficacious when containing higher proportions of mica to asphalt. For instance, the mica content by weight may run as high as 50% or even more. Moreover, the composition comprising my invention, because of the size of the ilow when subjected to heat. In addition, when the mica akes are too small, the resulting shingle does not partake of the characteristics of the mica as to strength and resistance to ilexure.

Mica as a constituent of a shingle is far superior to wood chips, for instance, since the latter, due to its resinous content, does not form as perfect a bond with the asphalt as does the mica. Moreover, the resulting shingle would not be ilreproot and moisture resistant. Slate chips mixed with asphalt are not equivalent to mica since they possess no appreciable degree of flexibility and more over tend to separate from the asphalt when the shingle is subjected to heat.

I claim as my invention:

1. A composition shingle comprising mica flakes of from approximately 4 to 40 mesh and asphalt, the mica ilakes being bound together in the form of an overlapping structure by relatively thin lms of asphalt.

2. A composition shingle comprising mica ilakes of from approximately 4 to 40 mesh and asphalt, the mica flakes being bound together in the form of a laminated tapered shingle by relatively thin illms of asphalt.

3. A composition shingle comprising mica ilakes having a mesh of from approximately 4 to 40 mesh and asphalt, the mica constituting about 30 percent and the asphalt about 70 percent by weight.

4. A .composition shingle comprising iiake mica and asphalt, the asphalt being present in relatively thin lms functioning to unite adjacent mica ilakes together in the form of an overlapping laminated structure, the mica flakes being oi a size greater than approximately 40 mesh.

5. A tapered composition shingle, comprising 'mica ilakes of from 4 to 40 mesh and asphalt,

the mica flakes being bound together in the form of an overlapping laminated structure by relatively thin illms of asphalt.

mixture being carried by a fibrous backing sheet.

SIGURD OLSEN. 

